The Arkansaw traveler., 1887-10-29
Compiled for The Arkdnsaw Traveller. SCIENTIFIC MISCELLANY


 There is, as Prof. Thompson re- marks, no assignable ''velocity," as this must vary with the current and the conductor. Wheatstone, in 1888, seemed to show transmission velocity of 288,000 miles a second through copper wire, but in late experiments signals were sent over ordinary tele- graph wires on poles, and had rate of only 14,000 to 16,600 miles. With wires near the earth the velocity was 12,000 miles, but reached 24,000 on very high wires.
 A DEUCE OF NEW ELEMENTS Rapid as has been the increase in the number of supposed elementary sub stances during the last few years, sober scientific men have hardly been prepared for the addition of more than a dozen new elements to the list in a single announcement, yet the discovery is reported on the authority of Messrs. Kruss and Nilsson, Swedish chemists of highest repute. Their researches have been carried out upon the nitrates of the rare earths contained ip Se orite, wohlerite, cerite, ferguso' R and euxenite, and have been Tor ~ d labo- rious. The spectroscopic W ence pre- sented by these inve. .tions has made the conclusion W sitable that didymium consists oX not less than nine distinct elements, holmium of seven, erbium of two, and samaritan of two.
 ELECTRICITY FROM FUEL.-Though the problem of converting heat di- rectly into electricity has received much attention, as its great import ance would warrant, no thermo bat tery has yet been capable of returning one per cent of the energy represented by the fuel applied to it. Mir. Edison, however, in his "pyromagnetic gen. erator of electricity" as described at the recent meeting of the American Association for the Advancement of Science, believes himself able to get electric power directly from coal with an economy equal to, and probably greatly exceeding, that of the indirect method of ordinary dynamos. His apparatus is based on the principle that the magnetic metals-iron, nickel and cobalt-lose their magnetizability when moderately heated, the heating and cooling of these metals in mag netic field causing variations in their magnetism which produce an electric current in surrounding coil of wire.
 THE FATE OF WoRLDS.-Thee earth, says lamarion, was born; it will die. It will die when it's vital elements have been spent, or perhaps by the extinction of the sun, in whose rays it's existence is suspended. It may die by the shock of a celestial body which it might meet in its path, but this end of the world is the most improbable of all. It may die, we say, by the slow absorption of it's clements. In truth, it is probable that the water and the air are diminishing. The ocean, like the atmosphere, appears to have been much more considerable than at present. The crust of the earth is penetrated by the waters, which combine chemically with the rocks. It is almost certain that the interior temperature of the globe at ten kilometres (about six miles) of depth reaches the boiling point and impedes further descent of the wa ters; but the absorption will con- tinue with the cooling of the globe. The oxygen, nitrogen and carbonic acid, which compose our atmosphere, appear to suffer likewise slow ab- sorption.
 CLOUD -MEAsURING.-The most i'm portant work in the measurement of clouds is now done at the University of Upsala, Sweden, by Messrs. Ekholm and Hagstrom. When opportunity offers, the heights of clouds are deter mined thrice daily by simultaneous observations at two telephonically- connected stations about mile apart. The angles of conspicuous points are carefully noted by means of specially adapted instruments, giving much more satisfactory data for fixing the distances than have been obtained by the photographic method attempted at Kew. The greatest height of any cloud yet measured is 4S,sO0 feet, and the highest velocity is 112 miles an hour for cloud at 28,OO0 feet. The most important result thus far reached from these measurements is the fact that clouds are quite regulary distrib- uted in three layers, the mean sum- mer levels for Upsala being low clouds-stratus, cumulus, cumulo- nimbus, 2,00o-6,000 feet: middle clouds-strato-cirrus, 12,000-15, ,000 feet; high clouds-cirrus. cirro-stra- tus, cirro-cumulus, 20,000-27 .ooo feet.
 A CHEMICAL ANoMALY.-An aston- ishing result has been reached by Dr.